Determination of the probabilities of spontaneous fission in U233, U235, and Am243

The periods of spontaneous fission were determined for urnaium and americium by means of fission-fragment detectors in the form of glass plates; these were: (1.2±0.3)·10¹⁷ years for U²³³, (3.5±0.9)·10¹⁷ years for U²³⁵, (3.3±0.3)·10¹³ years for Am²⁴³. An attempt was made to systematize experimental data on the spontaneous-fission periods of odd-even and even-odd nuclei.Translated from Atomnaya Énergiya, Vol. 20, No. 4, pp. 315–317, April, 1966.